Check iteration

Corrected a bug in generator_servo which meant that the efficiency was not initiated such that the mechanical torque could become max at the initial time step because eta is used for a division with the electrical torque demand

Blade stuck extended with the option to let blade 1 be stuck at its current angle. If you set the stuck angle (input 10) to numerically more than 90 deg then blade 1 will remain at its current angle.

adding to repository filter, flap servo, generator servo, mechanical brake, pass stop filter, and pitch servo